DVCC系列产品的88部分(含DV598JH/DV8086JH)的0832和8255来
 产生方波和正弦波
 接线:8255CS和DACS接到070-07F，PC0接开关，ADCS接060-06F，
  IN0接到W1。
 加载执行程序，用示波器查看 0832输出 AOUT
   	 CODE SEGMENT
  	 ASSUME CS:CODE
  	 ADPORT   EQU 0060H
  	 DAPORT	 EQU 0070H
  	 IOBPT	 EQU 0071H
  	 IOCPT	 EQU 0072H
  	 IOCONPT  EQU 0073H
  	 CONTPORT EQU 00DFH
 	 DATAPORT EQU 00DEH
  	 ST11     EQU  START
START:  CALL GETPC
        JMP DACONTORL
GETPC:  MOV BX,SP       ;取得开始IP地址子程序
        MOV AL,DS:[BX+0]
        MOV AH,DS:[BX+1]
        SUB AX,3
        MOV ES,AX
        RET

DACONTORL: MOV DX,ADPORT
        MOV AL,0H
        OUT DX,AL
        MOV AL,89H
	MOV DX,IOCONPT
	OUT DX,AL        ;初始化8255
        CALL LEDDISP
        MOV BX,ES
DACON1: MOV DX,DAPORT    ;正弦波产生
        MOV AL,CS:[BX+DATA2]
        OUT DX,AL
        CALL DELAY1
        MOV DX,IOCPT
	IN  AL,DX         ;取得8255状态
        CMP AL,0H
        JE  FANGBO
	INC BL
        MOV AL,BL
        CMP AL,63
        JE  DACON2
        INC BL
        JMP DACON1
DACON2: MOV BX,ES
	JMP DACON1

FANGBO: CMP BH,1          ;方波产生
	JE  FAN1
        MOV AL,0
	MOV BH,1
        JMP FAN2
FAN1  : MOV AL,0FFH
	MOV BH,0
FAN2  : MOV DX,DAPORT
        OUT DX,AL
        MOV DX,IOCPT
	IN  AL,DX         ;取得8255状态
        CMP AL,1
        JE  DACON1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        CALL DELAY1
        JMP FANGBO

DELAY1: PUSH CX          ;延时子程序1
        MOV DX,ADPORT
        IN  AL,DX
        MOV CL,AL
        MOV AL,0
        OUT DX,AL
        MOV AL,CL
        MOV CL,4         ;移位数
        SAR AL,cl
        AND AL,0FH
        ADD AL,1
        MOV CL,AL
        MOV CH,0
DELA2:  CALL DELAY2
	LOOP DELA2
        POP CX
	RET

DELAY2: PUSH CX          ;延时子程序2
 	MOV CX,8
DELA1:	LOOP DELA1
        POP CX
	RET

LEDDISP:MOV AL,90H      ;显示子程序
	MOV DX,CONTPORT
	OUT DX,AL
	MOV BYTE PTR DS:[0600H],00
        MOV BX,ES
LED1:	CMP BYTE PTR DS:[0600H],07H
	JA  LED2
	MOV AL,CS:[BX+DATA1]
	MOV DX,DATAPORT
	OUT DX,AL
	INC BX
	ADD BYTE PTR DS:[0600H],01H
	JNZ LED1
LED2:	RET
DATA1   DB  6DH,6DH,5BH,7FH,5BH,4FH,7FH,3FH  ;LED显示0832--3
DATA2   DB  143,153,165,177,189,200,210,219,228,235,242,247,251,254,255,255
        DB  254,252,249,244,238,231,223,214,204,193,182,170,158,146,133,120
        DB  107,95 ,83 ,71 ,60 ,49 ,39 ,31 ,23 ,16 ,10 ,6  ,2  ,0  ,0  ,0
        DB  2  ,5  ,9  ,14 ,21 ,29 ,37 ,47 ,57 ,68 ,80 ,92 ,104,117,130,140 ;SIN正弦波数据表
CODE ENDS
END START